Technical Field
The present disclosure relates to a contactless power supply system including power supply pads and a filter circuit having an inductor coil and connected to the power supply pads, in which the power supply pads are located face-to-face and electric power is transmitted from one power supply pad to the other power supply pad in a contactless manner.
Background Art
Contactless power supply systems are known, which include power supply pads and a filter circuit having an inductor coil and connected to the power supply pads. In such a contactless power supply system, the power supply pads are located face-to-face and electric power is transmitted from one power supply pad to the other power supply pad in a contactless manner. For example, JP-A-2009-528812 discloses an inductively coupled power transfer system.
The inductively coupled power transfer system includes a transformer, a loop conductor, and a pickup coil. A filter circuit is configured using the leakage inductance of the transformer. The transformer insulates an alternating current supplied to the loop conductor, and converts the current into a predetermined voltage. The filter circuit removes predetermined frequency components included in the insulated alternating current. When the pickup coil is allowed to face the loop conductor, the pickup coil is magnetically coupled to the loop conductor. As a result, electric power is transmitted from the loop conductor to the pickup coil in a contactless manner. The loop conductor and the pickup coil correspond to the power supply pad. The leakage inductance of the transformer corresponds to the inductance of the inductor coil.
Patent Literature 1: JP-A-2009-528812
In the case where a filter circuit is used in a contactless power supply system, typically, an inductor coil having a core is used.
On the other hand, in the above-described inductively coupled power transfer system, the filter circuit is configured using the leakage inductance of the transformer. Thus, it is not necessary to separately provide an inductor coil having a core as a filter circuit, and the system can be downsized.
However, the inductively coupled power transfer system is applicable only to a system including a transformer. If inductance necessary for a filter circuit is large, leakage inductance of the transformer has to be increased, causing the efficiency of the transformer to be lowered.